Device for applying binding strips to bags of rectangular cross section



Dec. 3, 1963 1-. JUNGMAYR 3,112,679

DEVICE FOR APPLYING BINDING STRIPS TO BAGS OF RECTANGULAR CROSS SECTIONFiled Jan. 16, 1961 2 Sheets-Sheet 1 Fig. 1

Dec. 3, 1963 I T. JUNGMAYR 3,112,679

DEVICE FOR APPLYING BINDING STRIPS TO BAGS 0F RECTANGULAR CROSS SECTION2 Sheets-Sheet 2 Filed Jan. 16, 1961 Fig. 3

Fig. 4

United States Patent F 3,112,679 DEVICE FER APPLYWG EENDZNG STREPS T0BAGS OF RECTANGULAR CRGSS SEQTKGN Theodor .lungmayr, Stuttgart-Nerd,Germany, assignor to Firma Fr. Hesser,Maschiuenfahrik-Ahtiengesellsshaft, Stuttgart-Bad Cannstatt, Germany, acorporation of Germany Filed Kan. 16, 1%1, Ser. No. 32,863 Claimspriority, application Germany Jan. 27, 196i) 8 Claims. (Cl. 93-45) Thisapplication reiates to apparatus and methods for forming slots in a bagthrough which a fastening strip may be introduced to permit forming aclosure for the bag.

In the case of bags having a folded over closure at the mouth of the bagand a fastening or binding strip to keep it folded over, it is known topass the strip through the narrower sides of the bag in the immediatevicinity of the front or rear wall of the latter.

It is an object of this invention to present a device which, in a verysimple fashion, permits the completely automatic application of bindingstrips in this way to the bag mouth.

A further object is to enable such application to take place withoutdetracting from the rate of operation of the machine with which it isused. Such a machine is advantageously an automatic packaging machine.

For this purpose the device according to this invention ischaracterised, in accordance with a primary feature, by two pairs ofcutting tools in scissors arrangement which are adapted to be introducedinto the mouth of a packaging bag of rectangular cross section, theprinciple being that each tool pair, in operation, is adapted to engageone of the mutually opposed sides of the bag and to form a slot or slitin this side; further, each pair of cutting tools is intended at thesame time to form guide means for a binding strip which is to be pushedthrough the slit. The guide means can be augmented by a plate whichextends between the two pairs of cutting tools and is disposed parallelto the adjacent side of the bag between the aforesaid opposed sides.

An arrangement of this character has the important advantages that theslits required for insertion of the binding strip are made in theintended bag walls before the binding strip is actually introduced,thereby positively precluding tearing of these walls such as frequentlyoccurs when the slits are made only by the binding strips themselves.

In a preferred arrangement the pairs of cutting tools are disposed on acommon carrier, are spaced from each other by a specific amountcorresponding to the distance between the slit sides of the bag, andeach comprises a preferably curved, knife-like blade and an associatedanvil, serving as a counter knife, this blade and anvil being oppositelypivotable about a common axis.

The anvils will advantageously each be provided at the end with asurface recess of groove form of a width corresponding to that of theassociated cutting blade and forming a guide for the binding strip whichis to be pushed in after the cutting procedure.

The guide plate referred to is best adjustably secured in the device sothat, in conjunction with the recesses in the anvils, there will be aguide means at all sides for the inserted binding strip, and in additionthere will be a support for the wall of the bag adjacent the bindingstrip.

Moreover at least the end part of the guide bar located at the entry forthe binding strip can be rounded or bevelled and thereby form, inconjunction with the cutting blade at this side, a sort of introductoryfunnel for the inserted binding strips.

Yet another feature of the invention lies in the rounding or bevellingof that part of the surface recess in the anvil at the outer side, whichfaces the entrance, such that this part of the recess is enlargedfunnelwise towards the inlet side.

A preferred embodiment of the device according to the invention isdescribed below by way of example in reference to the accompanyingdiagrammatic drawings, without the invention being restricted to thedetails shown in this example.

in the drawings:

FIGURE 1 is a front view of the device, with the guide plate omitted,

FEGURE 2 is a broken plan view of the device seen in FIGURE 1,

FEGURE 3 is a side view of the device, and

FIGURES 4 and 5 show the bag in respective view in various phases offormation of the closure.

In the preferred embodiment of the invention illustrated there is a setof tools which is detachably or replaceably associated with an automaticpacking machine (part only of which is shown) and is adapted to be movedagainst and away from the bag mouth 1. This tool set substantiallycomprises two pairs of cutting tools, the tools of each being movableone relative to the other in scissors fashion. Each such pair consistsof a curved cutting blade 2 and an associated counter blade or anvil 3.The cutting blades 2 and anvils 3 are secured to bellcrank levers 4- and5 respectively, which are relatively pivotable in pairs, aboutrespective common pivots A on a carrier 6 which supports the completeset of tools.

Preferably, carrier 6 has a coupling element B which is arrangedcentrally between the two said pivots A and serves to transmit to thetool sets the required movements thereof relatively to the mouth of thebag to be pierced. These movements of the tool set are obtained, througha cam plate 15 and a lever 16, which is articulated to the couplingelement B, from the main drive of the machine. Preferably, element B ismovably mounted in a slideway 13 on the machine frame 17 at theappropriate station.

The anvils 3 of the paired tools have grooves 8 aligned with theassociated cutting blades 2, and the cutting edges 7 of the latter arearranged to penetrate partially into these grooves during their movementrelatively to the anvils 3.

To make the slits or perforations in the walls of the bag required forinsertion of a binding or fastening strip 9 as stated, the tool set ismoved towards the open mouth of the bag by tool carrier ti and thecoupling element B so that the two narrower sides of the open mouth ofthe bag pass between the respective pairs of anvils 3 and the cuttingblades 2 (see FIGURE 2). The anvils 3 and the cutting blades 2 are thenpivotally moved toward one another by the associated bellcrank levers 4and 5 so that the anvils 3 hear, from the inside, against the narrowersides of the bag 1 and present counter edges to the cutting edges 7 ofthe blades 2 piercing the walls of the bag.

To enable the cutting blades 2 and the anvils 3 to be operatedsimultaneously from a single initiating movement only, the bellcranklevers 4 and 5 thereof are provided, via the pivots A thereof, withangularly offset ex tensions 2d, 21 which are coupled together in pairsby links 22, viz. the bellcrank lever 4 of the cutting knife 2 of onepair of tools is coupled to the bellcrank lever 5 of the anvil 3 of theother pair of cutting tools. Moreover, the two bellcrank levers 4i, 5beneath the tool carrier 6 are pivotally connected together by means ofa further link 23, extending transversely between the two pivots A, toproduce a motion counter to that first applied. This movement isimparted to the extension 21 of one bell- =3 crank lever which carries aroller 24, from a U-sh'aped part 25 surrounding the roller 24. This part25 is fastened to a lever 26 which is operated from the main drive ofthe machine through a face cam 27.

In the position of the cutting tools 2, 3 illustrated in FIGURES 1 and 2of the drawings the binding strip 9, made of a suitable material, is fedin the direction of arrow a, by means of a feed device associated withthe machine and not here shown. The feeding device is well known andneeds no further amplification. This binding strip 9 passes through thetwo slots made in the walls of the bag, the cutting blades 2 in thegrooves 8 of the anvils 3 providing guide means for this purpose. It isimmaterial whether binding strips already cut to length are fed in orwhether an endless strip is inserted from a reel or other supply to therequired length and then cut off.

After the binding strip 9 has been inserted in the prescribed fashion,the tool set, under the influence of the cam disc 15, makes a returnmovement in the opposite direction out of the mouth of the 'bag, as soonas engagement has been broken between the cutting tools 2, 3 and thewalls of the bag. The bag equipped with a binding strip and held in acontainer 28 of the conveyor mechanism of the machine, for example aconveyor chain 29, can now be carried in a manner as shown in FIG- URE 4to a further operating station in the machine, where it can bedischarged from the latter after its closure and sealing of the closureby turning over the ends of the binding strip 9. A closed bag withturned over ends is shown in FIGURE 5.

It has proven advantageous to assist the guidance of the binding strip9, during its insertion into the slits in the walls of the bag, by anadditional guide plate 11. This plate 11 is arranged on the machine,from case to case stationary or preferably adjustable by means of screws30 in relation to the ends of the anvils and in front of the bag mouth1, and has a rounded portion 1% particularly at the entrance end for thebinding strip 9 but conveniently also at the departure end for the same,and this rounded portion, in co-operation with the curved outer surfaceof the related cutting blade 2, and also in conjunction with therecesses in the anvils 3, constitute flared inlets for the bindingstrips 9.

Advantageously, to ensure proper guiding of the binding strip 9 into thetwo slits in the bag wall, a flared enlargement is provided at the inletend of the groove 8 of the anvil 3 which is to accept the free leadingend of the binding strip 9 after the passage of the latter through thefirst slit in the bag wall.

What I claim is:

1. Apparatus for forming slots in a bag adjacent an open end thereof topermit installation of a fastening strip into said slots, said apparatuscomprising a carrier vertically movable towards the open end of the bag,two pairs of cutting tools mounted on said carrier in spaced locationfor providing slots in said bag, each pair of tools comprising first andsecond arms, a common pivot connecting said arms to said carrier, acutting blade on one of said arms, an anvil on the other of the arms,the common pivots of the tool pairs being spaced on said carrier, meansfor moving the carrier and the tools therewith relative to the bag to aposition corresponding to a desired position of the slots, the baghaving end walls, the anvil and the cutting blade of each tool pairbeing respectively located on opposite sides of the end walls of thebag, means for producing relative movement between the blade and anvilof each pair of tools to form said slots in the walls of the bag, saidbag with the thusly formed slots therein being adapted for accommodatingand supporting a fastening strip therein, and means cooperating with thecutting tools to form a guide for entry of the fastening strip into saidslots.

2. Apparatus as claimed in claim 1, wherein the means for producingrelative movement between the #blade and anvil of each tool pairincludes a mechanical link-age connected to the tool pairs to produceopposite pivotal movement of the cutting blade and anvil of each cuttingtool to move each blade into a groove provided in the associated anvil.

3. A device as claimed in claim 1, in which the cutting blade and anvilof each tool pair are cooperatingly formed to provide a guideway for thefastening strip.

4. Apparatus as claimed in claim 1, wherein the means forming a guidewith the cutting tools comprises a guide member positioned exteriorly ofthe bag and adjacent the cutting tools with the latter in position toprovide the slots, said guide member and cutting tools forming aguideway for said fastening strip.

5. Apparatus as claimed in claim 4, comprising means adjustablysupporting said guide member for movement towards and away from saidcutting tools.

6. Apparatus as claimed in claim 1, wherein the means for forming aguide for the fastener strip comprises a guide member positionedexteriorly of the bag and adjacent the cutting tools with'the latter inposition to provide the slots, each said anvil having a groove foraccommodating the corresponding cutting tool, said guide memberextending beyond the groove of each of the anvils to form with saidgroove and the corresponding cutting tool a guideway for said fastenerstrip.

7. Apparatus as claimed in claim 6, wherein said groove of one of theanvils is flared to facilitate entry of the fastening strip thereintoand into the corresponding slot.

8. Apparatus as claimed in claim 1, wherein said guide member is ofreduced thickness beyond the bag walls to form a flared inlet tofacilitate entry of said fastening strip into said guideway.

References Cited in the file of this patent UNITED STATES PATENTS CanadaMay 6, 1958

1. APPARATUS FOR FORMING SLOTS IN A BAG ADJACENT AN OPEN END THEREOF TOPERMIT INSTALLATION OF A FASTENING STRIP INTO SAID SLOTS, SAID APPARATUSCOMPRISING A CARRIER VERTICALLY MOVABLE TOWARDS THE OPEN END OF THE BAG,TWO PAIRS OF CUTTING TOOLS MOUNTED ON SAID CARRIER IN SPACED LOCATIONFOR PROVIDING SLOTS IN SAID BAG, EACH PAIR OF TOOLS COMPRISING FIRST ANDSECOND ARMS, A COMMON PIVOT CONNECTING SAID ARMS TO SAID CARRIER, ACUTTING BLADE ON ONE OF SAID ARMS, AN ANVIL ON THE OTHER OF THE ARMS,THE COMMON PIVOTS OF THE TOOL PAIRS BEING SPACED ON SAID CARRIER, MEANSFOR MOVING THE CARRIER AND THE TOOLS THEREWITH RELATIVE TO THE BAG TO APOSITION CORRESPONDING TO A DESIRED POSITION OF THE SLOTS, THE BAGHAVING END WALLS, THE ANVIL AND THE CUTTING BLADE OF EACH TOOL PAIRBEING RESPECTIVELY LOCATED ON OPPOSITE SIDES OF THE END WALLS OF THEBAG, MEANS FOR PRODUCING RELATIVE MOVEMENT BETWEEN THE BLADE AND ANVILOF EACH PAIR OF TOOLS TO FORM SAID SLOTS IN THE WALLS OF THE BAG, SAIDBAG WITH THE THUSLY FORMED SLOTS THEREIN BEING ADAPTED FOR ACCOMMODATINGAND SUPPORTING A FASTENING STRIP THEREIN, AND MEANS COOPERATING WITH THECUTTING TOOLS TO FORM A GUIDE FOR ENTRY OF THE FASTENING STRIP INTO SAIDSLOTS.